Sudan’s army has rejected to attend the peace talks in the meeting of the East African bloc that aimed to end three months of fighting in the North African country.

This came after the East African bloc known as the Intergovernmental Authority on Development (IGAD) invited both the Sudanese army and the rival paramilitary Rapid Support Forces (RSF) to its meeting in Ethiopia's capital on Monday.

Sudan’s army, however, accused Kenya, which chaired the talks, of favoring the RSF.

The fighting in Sudan began in mid-April over a power struggle between army chief, Abdel Fattah al-Burhan, and his former deputy, Mohamed Hamdan Dagalo, who commands the RSF.

Neither Burhan nor Dagalo personally attended the talks in Addis Ababa, but the RSF sent a representative to the quartet meeting, which was attended by Kenya, South Sudan, Djibouti and Ethiopia.

The quartet issued a communique following the Monday meeting, deploring "the regrettable absence of the delegation of the Sudanese Armed Forces in spite of the invitation and confirmation of attendance."

The quartet said it had agreed to "mobilize and concentrate the efforts of all stakeholders towards delivering a face-to-face meeting between the leaders of the warring parties."

It also called on the rival generals to "immediately stop the violence and sign an unconditional and indefinite ceasefire."

The meeting came a day after the United Nations Secretary General Antonio Guterres warned that Sudan is on the brink of a full-fledged civil war, which may spill over into neighboring countries and threaten stability of the entire region.

Guterres "remains deeply concerned that the ongoing war between the armed forces has pushed Sudan to the brink of a full-scale civil war, potentially destabilizing the entire region," the UN chief’s spokesperson, Farhan Haq, said in a statement.

While the meeting was going on, residents reported battles and airstrikes in several areas of Sudan’s capital city of Khartoum, some reporting rockets falling on civilians' houses.

Witnesses also reported fighting in El-Obeid, the capital of North Kordofan and a commercial hub some 350 kilometers (220 miles) south of Khartoum.

According to the latest figures, around 3,000 people have been killed in Sudan's conflict so far.

The International Organization for Migration says nearly three million people have been displaced by the fighting, among them almost 700,000 who have fled to neighboring countries, especially Chad and Egypt.